Question

You have three lenses L1, L2 and L3 of powers +10D, +5D and -10D respectively.
a. State the nature and focal length of each lens.
b. Explain which of the three lenses will form a virtual and magnified image of an object
placed at 15 cm from the lens.
c. Draw the ray diagram in support of your answer.
this a grade 10 question pls help me!!! emergency
who answers the question correctly will be matked brainliest

Answer 1

Explanation:

Lens I1 ,

P=+10D

So P=1/f (in metre )

f =0.1 metre and its convex lens since focal length is positive

In Lens I2,

P=+5D

f=1/P

f=1/5 =0.2 metre and its again convex lens .

In Len I3,

P=-10D

f=1/D

f=1/-10

f=-0.1 metre and its concave lens since focal length is negative .

(Sign Convetion is important in these questions and it's very easy